Yokoyama, Sumi*; Takahashi, Tomoyuki*; Ota, Masakazu; Kakiuchi, Hideki*; Sugihara, Shinji*; Hirao, Shigekazu*; Momoshima, Noriyuki*; Tamari, Toshiya*; Shima, Nagayoshi*; Atarashi-Andoh, Mariko; et al.
Plasma and Fusion Research (Internet), 14(Sp.2), p.3405099_1 - 3405099_4, 2019/06
The Large Helical Device of the National Institute for Fusion Science started D-D experiments in 2017. To ensure the safety of the facility, it is important to develop evaluation methods for environmental tritium transfer. Tritiated water (HTO) in atmosphere and soil is transferred to plants, and organically bound tritium (OBT) is formed by photosynthesis. Prediction of OBT formation is important, because OBT accumulates in plants and causes dose through ingestion. The objective of this study is to estimate environmental tritium transfer using a simple compartment model and practical parameters. We proposed a simple compartment model consisting of air-soil-plant components, and tried to validate the model by comparison with a sophisticated model, SOLVEG. In this study, we plan to add wet deposition to the model and obtain parameters from measurements of soil permeability and tritium concentrations in air, soil and plants. We also establish rapid pretreatment methods for OBT analysis.
Sugihara, Shinji*; Tanaka, Masahiro*; Tamari, Toshiya*; Shimada, Jun*; Takahashi, Tomoyuki*; Momoshima, Noriyuki*; Fukutani, Satoshi*; Atarashi-Andoh, Mariko; Sakuma, Yoichi*; Yokoyama, Sumi*; et al.
Fusion Science and Technology, 60(4), p.1300 - 1303, 2011/11
The purpose of this study is to develop the technique to evaluate the environmental tritium behavior of the nuclear facility origin. Tritium concentrations of river water, precipitation and ground water around the NIFS site were determined by low background liquid scintillation measurement system combined with the electrolysis using solid polymer electrolyte. The electric conductivity and flow rate of the river and isotopic ratio of oxygen and hydrogen of water samples were also measured. The tritium concentrations in precipitation showed the seasonal variation and the range were 0.09-0.78 Bq/L. The tritium concentrations of river water and ground water were almost constant, 0.34 and 0.24 Bq/L respectively. The simple dynamic model for the site around the NIFS facilities was developed using measured data, and the behavior of tritium was simulated.
Momoshima, Noriyuki*; Hayashi, Takumi
Purazuma, Kaku Yugo Gakkai-Shi, 85(1), p.36 - 40, 2009/01
no abstracts in English
Amano, Hikaru; Yamamichi, Miwako*; Baba, Masami*; Momoshima, Noriyuki*; Sugihara, Shinji*; Ueda, Yusuke*; Nakamura, Yasuhiro*
JAEA-Conf 2008-003, p.84 - 87, 2008/04
no abstracts in English
Shima, Shigeki*; Gasa, Shinichi*; Amano, Hikaru; Nagao, Seiya*; Yamamoto, Masayoshi*; Momoshima, Noriyuki*; Furukawa, Masahide*; Kimura, Hideki*; Kawamura, Hisao*
JAEA-Conf 2008-003, p.28 - 31, 2008/04
Concentrations of I in surface seawater around Japan were approximately 210atoms/L in literatures. However, the atomic ratio of iodine to cesium was ten times as high as that of the global fallout. The origin of I in the water columns seems to be difficult to be explained by only the global fallout. Discharge from European plants was one of the possible origins of iodine from the standpoint of air mass trajectory analysis. Concentration of I in rain water was 10 times higher than that in surface seawater. Anthropogenic inorganic iodine in surface seawater predominantly dissolves as an iodide ion (I).
Kokubu, Yoko; Momoshima, Noriyuki*; Hirose, Katsumi*; Tagami, Keiko*; Takamiya, Koichi*
no journal, ,
Just after an accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP), data of radionuclides released from the FDNPP were measured for environmental samples by some researchers at individual research institute and university. However a comprehensive database including these data is not constructed now. Working group of the Japan Society of Nuclear and Radiochemical Sciences decided to construct a comprehensive database of data of the radionuclides in environmental samples. This database contains data such as sampling location, sampling method, sampling times, type of measurement system, concentrations of the radionuclides and others in the publications/reports and unpublished issues. Researchers input the data in a dedicated Excel sheet. The working group verifies and registers the data in the database, and then summarizes them in a scientific report.